Incorrect query parameters can hurt you

[restless]

Recently checking my rankings for come keywords and I saw that my site was listed like this

http://www.example.com/index.php
description here

indented >> http://www.example.com/index.php?A=B
indented >> description here

They are the exact same page and I've never had such paramaters as
?A=B I do have other parameters but not these, and because it's a dynamic page of course it will show content. Could my competition have submited the 2nd url to google in the hope that I would get penalized for duplicate content?

Should my code now be checking for expected parameters because of this? That will be headache, you have to make a list of valid parameters for every dynamic page.

[edited by: tedster at 12:50 am (utc) on June 3, 2008]
[edit reason] switch to example.com - it cannot be owned [/edit]

[tedster]

First, there's a great thread in our Apache Forum that may inspire your work. It covers many areas including query strings. If you address sll of the issues in there, you'll lock up your site pretty tight.

A guide to fixing duplicate content & URL issues on Apache [webmasterworld.com]

Beyond that, yes -- query string parameters can be a souorce of problems on all search engines. I'm surprised that your page wasn't filtered out as a duplicate, but strange things do happen. It still may disappear.

Whether this was intentional ranking sabotage and done by whom may be hard to discover. But it doesn't matter a lot once you've plugged the hole -- except, of course, to watch out for other nonsense.